xref: /openbmc/linux/net/tipc/node.c (revision 842ed298)
1 /*
2  * net/tipc/node.c: TIPC node management routines
3  *
4  * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
5  * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the names of the copyright holders nor the names of its
17  *    contributors may be used to endorse or promote products derived from
18  *    this software without specific prior written permission.
19  *
20  * Alternatively, this software may be distributed under the terms of the
21  * GNU General Public License ("GPL") version 2 as published by the Free
22  * Software Foundation.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #include "core.h"
38 #include "link.h"
39 #include "node.h"
40 #include "name_distr.h"
41 #include "socket.h"
42 #include "bcast.h"
43 #include "monitor.h"
44 #include "discover.h"
45 #include "netlink.h"
46 #include "trace.h"
47 #include "crypto.h"
48 
49 #define INVALID_NODE_SIG	0x10000
50 #define NODE_CLEANUP_AFTER	300000
51 
52 /* Flags used to take different actions according to flag type
53  * TIPC_NOTIFY_NODE_DOWN: notify node is down
54  * TIPC_NOTIFY_NODE_UP: notify node is up
55  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
56  */
57 enum {
58 	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
59 	TIPC_NOTIFY_NODE_UP		= (1 << 4),
60 	TIPC_NOTIFY_LINK_UP		= (1 << 6),
61 	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
62 };
63 
64 struct tipc_link_entry {
65 	struct tipc_link *link;
66 	spinlock_t lock; /* per link */
67 	u32 mtu;
68 	struct sk_buff_head inputq;
69 	struct tipc_media_addr maddr;
70 };
71 
72 struct tipc_bclink_entry {
73 	struct tipc_link *link;
74 	struct sk_buff_head inputq1;
75 	struct sk_buff_head arrvq;
76 	struct sk_buff_head inputq2;
77 	struct sk_buff_head namedq;
78 	u16 named_rcv_nxt;
79 	bool named_open;
80 };
81 
82 /**
83  * struct tipc_node - TIPC node structure
84  * @addr: network address of node
85  * @kref: reference counter to node object
86  * @lock: rwlock governing access to structure
87  * @net: the applicable net namespace
88  * @hash: links to adjacent nodes in unsorted hash chain
89  * @inputq: pointer to input queue containing messages for msg event
90  * @namedq: pointer to name table input queue with name table messages
91  * @active_links: bearer ids of active links, used as index into links[] array
92  * @links: array containing references to all links to node
93  * @bc_entry: broadcast link entry
94  * @action_flags: bit mask of different types of node actions
95  * @state: connectivity state vs peer node
96  * @preliminary: a preliminary node or not
97  * @failover_sent: failover sent or not
98  * @sync_point: sequence number where synch/failover is finished
99  * @list: links to adjacent nodes in sorted list of cluster's nodes
100  * @working_links: number of working links to node (both active and standby)
101  * @link_cnt: number of links to node
102  * @capabilities: bitmap, indicating peer node's functional capabilities
103  * @signature: node instance identifier
104  * @link_id: local and remote bearer ids of changing link, if any
105  * @peer_id: 128-bit ID of peer
106  * @peer_id_string: ID string of peer
107  * @publ_list: list of publications
108  * @conn_sks: list of connections (FIXME)
109  * @timer: node's keepalive timer
110  * @keepalive_intv: keepalive interval in milliseconds
111  * @rcu: rcu struct for tipc_node
112  * @delete_at: indicates the time for deleting a down node
113  * @peer_net: peer's net namespace
114  * @peer_hash_mix: hash for this peer (FIXME)
115  * @crypto_rx: RX crypto handler
116  */
117 struct tipc_node {
118 	u32 addr;
119 	struct kref kref;
120 	rwlock_t lock;
121 	struct net *net;
122 	struct hlist_node hash;
123 	int active_links[2];
124 	struct tipc_link_entry links[MAX_BEARERS];
125 	struct tipc_bclink_entry bc_entry;
126 	int action_flags;
127 	struct list_head list;
128 	int state;
129 	bool preliminary;
130 	bool failover_sent;
131 	u16 sync_point;
132 	int link_cnt;
133 	u16 working_links;
134 	u16 capabilities;
135 	u32 signature;
136 	u32 link_id;
137 	u8 peer_id[16];
138 	char peer_id_string[NODE_ID_STR_LEN];
139 	struct list_head publ_list;
140 	struct list_head conn_sks;
141 	unsigned long keepalive_intv;
142 	struct timer_list timer;
143 	struct rcu_head rcu;
144 	unsigned long delete_at;
145 	struct net *peer_net;
146 	u32 peer_hash_mix;
147 #ifdef CONFIG_TIPC_CRYPTO
148 	struct tipc_crypto *crypto_rx;
149 #endif
150 };
151 
152 /* Node FSM states and events:
153  */
154 enum {
155 	SELF_DOWN_PEER_DOWN    = 0xdd,
156 	SELF_UP_PEER_UP        = 0xaa,
157 	SELF_DOWN_PEER_LEAVING = 0xd1,
158 	SELF_UP_PEER_COMING    = 0xac,
159 	SELF_COMING_PEER_UP    = 0xca,
160 	SELF_LEAVING_PEER_DOWN = 0x1d,
161 	NODE_FAILINGOVER       = 0xf0,
162 	NODE_SYNCHING          = 0xcc
163 };
164 
165 enum {
166 	SELF_ESTABL_CONTACT_EVT = 0xece,
167 	SELF_LOST_CONTACT_EVT   = 0x1ce,
168 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
169 	PEER_LOST_CONTACT_EVT   = 0x91ce,
170 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
171 	NODE_FAILOVER_END_EVT   = 0xfee,
172 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
173 	NODE_SYNCH_END_EVT      = 0xcee
174 };
175 
176 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
177 				  struct sk_buff_head *xmitq,
178 				  struct tipc_media_addr **maddr);
179 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
180 				bool delete);
181 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
182 static void tipc_node_delete(struct tipc_node *node);
183 static void tipc_node_timeout(struct timer_list *t);
184 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
185 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
186 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
187 static bool node_is_up(struct tipc_node *n);
188 static void tipc_node_delete_from_list(struct tipc_node *node);
189 
190 struct tipc_sock_conn {
191 	u32 port;
192 	u32 peer_port;
193 	u32 peer_node;
194 	struct list_head list;
195 };
196 
197 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
198 {
199 	int bearer_id = n->active_links[sel & 1];
200 
201 	if (unlikely(bearer_id == INVALID_BEARER_ID))
202 		return NULL;
203 
204 	return n->links[bearer_id].link;
205 }
206 
207 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
208 {
209 	struct tipc_node *n;
210 	int bearer_id;
211 	unsigned int mtu = MAX_MSG_SIZE;
212 
213 	n = tipc_node_find(net, addr);
214 	if (unlikely(!n))
215 		return mtu;
216 
217 	/* Allow MAX_MSG_SIZE when building connection oriented message
218 	 * if they are in the same core network
219 	 */
220 	if (n->peer_net && connected) {
221 		tipc_node_put(n);
222 		return mtu;
223 	}
224 
225 	bearer_id = n->active_links[sel & 1];
226 	if (likely(bearer_id != INVALID_BEARER_ID))
227 		mtu = n->links[bearer_id].mtu;
228 	tipc_node_put(n);
229 	return mtu;
230 }
231 
232 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
233 {
234 	u8 *own_id = tipc_own_id(net);
235 	struct tipc_node *n;
236 
237 	if (!own_id)
238 		return true;
239 
240 	if (addr == tipc_own_addr(net)) {
241 		memcpy(id, own_id, TIPC_NODEID_LEN);
242 		return true;
243 	}
244 	n = tipc_node_find(net, addr);
245 	if (!n)
246 		return false;
247 
248 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
249 	tipc_node_put(n);
250 	return true;
251 }
252 
253 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
254 {
255 	struct tipc_node *n;
256 	u16 caps;
257 
258 	n = tipc_node_find(net, addr);
259 	if (unlikely(!n))
260 		return TIPC_NODE_CAPABILITIES;
261 	caps = n->capabilities;
262 	tipc_node_put(n);
263 	return caps;
264 }
265 
266 u32 tipc_node_get_addr(struct tipc_node *node)
267 {
268 	return (node) ? node->addr : 0;
269 }
270 
271 char *tipc_node_get_id_str(struct tipc_node *node)
272 {
273 	return node->peer_id_string;
274 }
275 
276 #ifdef CONFIG_TIPC_CRYPTO
277 /**
278  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
279  * @__n: target tipc_node
280  * Note: node ref counter must be held first!
281  */
282 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
283 {
284 	return (__n) ? __n->crypto_rx : NULL;
285 }
286 
287 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
288 {
289 	return container_of(pos, struct tipc_node, list)->crypto_rx;
290 }
291 
292 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
293 {
294 	struct tipc_node *n;
295 
296 	n = tipc_node_find(net, addr);
297 	return (n) ? n->crypto_rx : NULL;
298 }
299 #endif
300 
301 static void tipc_node_free(struct rcu_head *rp)
302 {
303 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
304 
305 #ifdef CONFIG_TIPC_CRYPTO
306 	tipc_crypto_stop(&n->crypto_rx);
307 #endif
308 	kfree(n);
309 }
310 
311 static void tipc_node_kref_release(struct kref *kref)
312 {
313 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
314 
315 	kfree(n->bc_entry.link);
316 	call_rcu(&n->rcu, tipc_node_free);
317 }
318 
319 void tipc_node_put(struct tipc_node *node)
320 {
321 	kref_put(&node->kref, tipc_node_kref_release);
322 }
323 
324 void tipc_node_get(struct tipc_node *node)
325 {
326 	kref_get(&node->kref);
327 }
328 
329 /*
330  * tipc_node_find - locate specified node object, if it exists
331  */
332 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
333 {
334 	struct tipc_net *tn = tipc_net(net);
335 	struct tipc_node *node;
336 	unsigned int thash = tipc_hashfn(addr);
337 
338 	rcu_read_lock();
339 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
340 		if (node->addr != addr || node->preliminary)
341 			continue;
342 		if (!kref_get_unless_zero(&node->kref))
343 			node = NULL;
344 		break;
345 	}
346 	rcu_read_unlock();
347 	return node;
348 }
349 
350 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
351  * Note: this function is called only when a discovery request failed
352  * to find the node by its 32-bit id, and is not time critical
353  */
354 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
355 {
356 	struct tipc_net *tn = tipc_net(net);
357 	struct tipc_node *n;
358 	bool found = false;
359 
360 	rcu_read_lock();
361 	list_for_each_entry_rcu(n, &tn->node_list, list) {
362 		read_lock_bh(&n->lock);
363 		if (!memcmp(id, n->peer_id, 16) &&
364 		    kref_get_unless_zero(&n->kref))
365 			found = true;
366 		read_unlock_bh(&n->lock);
367 		if (found)
368 			break;
369 	}
370 	rcu_read_unlock();
371 	return found ? n : NULL;
372 }
373 
374 static void tipc_node_read_lock(struct tipc_node *n)
375 {
376 	read_lock_bh(&n->lock);
377 }
378 
379 static void tipc_node_read_unlock(struct tipc_node *n)
380 {
381 	read_unlock_bh(&n->lock);
382 }
383 
384 static void tipc_node_write_lock(struct tipc_node *n)
385 {
386 	write_lock_bh(&n->lock);
387 }
388 
389 static void tipc_node_write_unlock_fast(struct tipc_node *n)
390 {
391 	write_unlock_bh(&n->lock);
392 }
393 
394 static void tipc_node_write_unlock(struct tipc_node *n)
395 {
396 	struct net *net = n->net;
397 	u32 addr = 0;
398 	u32 flags = n->action_flags;
399 	u32 link_id = 0;
400 	u32 bearer_id;
401 	struct list_head *publ_list;
402 
403 	if (likely(!flags)) {
404 		write_unlock_bh(&n->lock);
405 		return;
406 	}
407 
408 	addr = n->addr;
409 	link_id = n->link_id;
410 	bearer_id = link_id & 0xffff;
411 	publ_list = &n->publ_list;
412 
413 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
414 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
415 
416 	write_unlock_bh(&n->lock);
417 
418 	if (flags & TIPC_NOTIFY_NODE_DOWN)
419 		tipc_publ_notify(net, publ_list, addr, n->capabilities);
420 
421 	if (flags & TIPC_NOTIFY_NODE_UP)
422 		tipc_named_node_up(net, addr, n->capabilities);
423 
424 	if (flags & TIPC_NOTIFY_LINK_UP) {
425 		tipc_mon_peer_up(net, addr, bearer_id);
426 		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
427 				     TIPC_NODE_SCOPE, link_id, link_id);
428 	}
429 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
430 		tipc_mon_peer_down(net, addr, bearer_id);
431 		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
432 				      addr, link_id);
433 	}
434 }
435 
436 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
437 {
438 	int net_id = tipc_netid(n->net);
439 	struct tipc_net *tn_peer;
440 	struct net *tmp;
441 	u32 hash_chk;
442 
443 	if (n->peer_net)
444 		return;
445 
446 	for_each_net_rcu(tmp) {
447 		tn_peer = tipc_net(tmp);
448 		if (!tn_peer)
449 			continue;
450 		/* Integrity checking whether node exists in namespace or not */
451 		if (tn_peer->net_id != net_id)
452 			continue;
453 		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
454 			continue;
455 		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
456 		if (hash_mixes ^ hash_chk)
457 			continue;
458 		n->peer_net = tmp;
459 		n->peer_hash_mix = hash_mixes;
460 		break;
461 	}
462 }
463 
464 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
465 				   u16 capabilities, u32 hash_mixes,
466 				   bool preliminary)
467 {
468 	struct tipc_net *tn = net_generic(net, tipc_net_id);
469 	struct tipc_node *n, *temp_node;
470 	struct tipc_link *l;
471 	unsigned long intv;
472 	int bearer_id;
473 	int i;
474 
475 	spin_lock_bh(&tn->node_list_lock);
476 	n = tipc_node_find(net, addr) ?:
477 		tipc_node_find_by_id(net, peer_id);
478 	if (n) {
479 		if (!n->preliminary)
480 			goto update;
481 		if (preliminary)
482 			goto exit;
483 		/* A preliminary node becomes "real" now, refresh its data */
484 		tipc_node_write_lock(n);
485 		n->preliminary = false;
486 		n->addr = addr;
487 		hlist_del_rcu(&n->hash);
488 		hlist_add_head_rcu(&n->hash,
489 				   &tn->node_htable[tipc_hashfn(addr)]);
490 		list_del_rcu(&n->list);
491 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
492 			if (n->addr < temp_node->addr)
493 				break;
494 		}
495 		list_add_tail_rcu(&n->list, &temp_node->list);
496 		tipc_node_write_unlock_fast(n);
497 
498 update:
499 		if (n->peer_hash_mix ^ hash_mixes)
500 			tipc_node_assign_peer_net(n, hash_mixes);
501 		if (n->capabilities == capabilities)
502 			goto exit;
503 		/* Same node may come back with new capabilities */
504 		tipc_node_write_lock(n);
505 		n->capabilities = capabilities;
506 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
507 			l = n->links[bearer_id].link;
508 			if (l)
509 				tipc_link_update_caps(l, capabilities);
510 		}
511 		tipc_node_write_unlock_fast(n);
512 
513 		/* Calculate cluster capabilities */
514 		tn->capabilities = TIPC_NODE_CAPABILITIES;
515 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
516 			tn->capabilities &= temp_node->capabilities;
517 		}
518 
519 		tipc_bcast_toggle_rcast(net,
520 					(tn->capabilities & TIPC_BCAST_RCAST));
521 
522 		goto exit;
523 	}
524 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
525 	if (!n) {
526 		pr_warn("Node creation failed, no memory\n");
527 		goto exit;
528 	}
529 	tipc_nodeid2string(n->peer_id_string, peer_id);
530 #ifdef CONFIG_TIPC_CRYPTO
531 	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
532 		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
533 		kfree(n);
534 		n = NULL;
535 		goto exit;
536 	}
537 #endif
538 	n->addr = addr;
539 	n->preliminary = preliminary;
540 	memcpy(&n->peer_id, peer_id, 16);
541 	n->net = net;
542 	n->peer_net = NULL;
543 	n->peer_hash_mix = 0;
544 	/* Assign kernel local namespace if exists */
545 	tipc_node_assign_peer_net(n, hash_mixes);
546 	n->capabilities = capabilities;
547 	kref_init(&n->kref);
548 	rwlock_init(&n->lock);
549 	INIT_HLIST_NODE(&n->hash);
550 	INIT_LIST_HEAD(&n->list);
551 	INIT_LIST_HEAD(&n->publ_list);
552 	INIT_LIST_HEAD(&n->conn_sks);
553 	skb_queue_head_init(&n->bc_entry.namedq);
554 	skb_queue_head_init(&n->bc_entry.inputq1);
555 	__skb_queue_head_init(&n->bc_entry.arrvq);
556 	skb_queue_head_init(&n->bc_entry.inputq2);
557 	for (i = 0; i < MAX_BEARERS; i++)
558 		spin_lock_init(&n->links[i].lock);
559 	n->state = SELF_DOWN_PEER_LEAVING;
560 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
561 	n->signature = INVALID_NODE_SIG;
562 	n->active_links[0] = INVALID_BEARER_ID;
563 	n->active_links[1] = INVALID_BEARER_ID;
564 	n->bc_entry.link = NULL;
565 	tipc_node_get(n);
566 	timer_setup(&n->timer, tipc_node_timeout, 0);
567 	/* Start a slow timer anyway, crypto needs it */
568 	n->keepalive_intv = 10000;
569 	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
570 	if (!mod_timer(&n->timer, intv))
571 		tipc_node_get(n);
572 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
573 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
574 		if (n->addr < temp_node->addr)
575 			break;
576 	}
577 	list_add_tail_rcu(&n->list, &temp_node->list);
578 	/* Calculate cluster capabilities */
579 	tn->capabilities = TIPC_NODE_CAPABILITIES;
580 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
581 		tn->capabilities &= temp_node->capabilities;
582 	}
583 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
584 	trace_tipc_node_create(n, true, " ");
585 exit:
586 	spin_unlock_bh(&tn->node_list_lock);
587 	return n;
588 }
589 
590 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
591 {
592 	unsigned long tol = tipc_link_tolerance(l);
593 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
594 
595 	/* Link with lowest tolerance determines timer interval */
596 	if (intv < n->keepalive_intv)
597 		n->keepalive_intv = intv;
598 
599 	/* Ensure link's abort limit corresponds to current tolerance */
600 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
601 }
602 
603 static void tipc_node_delete_from_list(struct tipc_node *node)
604 {
605 #ifdef CONFIG_TIPC_CRYPTO
606 	tipc_crypto_key_flush(node->crypto_rx);
607 #endif
608 	list_del_rcu(&node->list);
609 	hlist_del_rcu(&node->hash);
610 	tipc_node_put(node);
611 }
612 
613 static void tipc_node_delete(struct tipc_node *node)
614 {
615 	trace_tipc_node_delete(node, true, " ");
616 	tipc_node_delete_from_list(node);
617 
618 	del_timer_sync(&node->timer);
619 	tipc_node_put(node);
620 }
621 
622 void tipc_node_stop(struct net *net)
623 {
624 	struct tipc_net *tn = tipc_net(net);
625 	struct tipc_node *node, *t_node;
626 
627 	spin_lock_bh(&tn->node_list_lock);
628 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
629 		tipc_node_delete(node);
630 	spin_unlock_bh(&tn->node_list_lock);
631 }
632 
633 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
634 {
635 	struct tipc_node *n;
636 
637 	if (in_own_node(net, addr))
638 		return;
639 
640 	n = tipc_node_find(net, addr);
641 	if (!n) {
642 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
643 		return;
644 	}
645 	tipc_node_write_lock(n);
646 	list_add_tail(subscr, &n->publ_list);
647 	tipc_node_write_unlock_fast(n);
648 	tipc_node_put(n);
649 }
650 
651 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
652 {
653 	struct tipc_node *n;
654 
655 	if (in_own_node(net, addr))
656 		return;
657 
658 	n = tipc_node_find(net, addr);
659 	if (!n) {
660 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
661 		return;
662 	}
663 	tipc_node_write_lock(n);
664 	list_del_init(subscr);
665 	tipc_node_write_unlock_fast(n);
666 	tipc_node_put(n);
667 }
668 
669 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
670 {
671 	struct tipc_node *node;
672 	struct tipc_sock_conn *conn;
673 	int err = 0;
674 
675 	if (in_own_node(net, dnode))
676 		return 0;
677 
678 	node = tipc_node_find(net, dnode);
679 	if (!node) {
680 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
681 		return -EHOSTUNREACH;
682 	}
683 	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
684 	if (!conn) {
685 		err = -EHOSTUNREACH;
686 		goto exit;
687 	}
688 	conn->peer_node = dnode;
689 	conn->port = port;
690 	conn->peer_port = peer_port;
691 
692 	tipc_node_write_lock(node);
693 	list_add_tail(&conn->list, &node->conn_sks);
694 	tipc_node_write_unlock(node);
695 exit:
696 	tipc_node_put(node);
697 	return err;
698 }
699 
700 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
701 {
702 	struct tipc_node *node;
703 	struct tipc_sock_conn *conn, *safe;
704 
705 	if (in_own_node(net, dnode))
706 		return;
707 
708 	node = tipc_node_find(net, dnode);
709 	if (!node)
710 		return;
711 
712 	tipc_node_write_lock(node);
713 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
714 		if (port != conn->port)
715 			continue;
716 		list_del(&conn->list);
717 		kfree(conn);
718 	}
719 	tipc_node_write_unlock(node);
720 	tipc_node_put(node);
721 }
722 
723 static void  tipc_node_clear_links(struct tipc_node *node)
724 {
725 	int i;
726 
727 	for (i = 0; i < MAX_BEARERS; i++) {
728 		struct tipc_link_entry *le = &node->links[i];
729 
730 		if (le->link) {
731 			kfree(le->link);
732 			le->link = NULL;
733 			node->link_cnt--;
734 		}
735 	}
736 }
737 
738 /* tipc_node_cleanup - delete nodes that does not
739  * have active links for NODE_CLEANUP_AFTER time
740  */
741 static bool tipc_node_cleanup(struct tipc_node *peer)
742 {
743 	struct tipc_node *temp_node;
744 	struct tipc_net *tn = tipc_net(peer->net);
745 	bool deleted = false;
746 
747 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
748 	if (!spin_trylock_bh(&tn->node_list_lock))
749 		return false;
750 
751 	tipc_node_write_lock(peer);
752 
753 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
754 		tipc_node_clear_links(peer);
755 		tipc_node_delete_from_list(peer);
756 		deleted = true;
757 	}
758 	tipc_node_write_unlock(peer);
759 
760 	if (!deleted) {
761 		spin_unlock_bh(&tn->node_list_lock);
762 		return deleted;
763 	}
764 
765 	/* Calculate cluster capabilities */
766 	tn->capabilities = TIPC_NODE_CAPABILITIES;
767 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
768 		tn->capabilities &= temp_node->capabilities;
769 	}
770 	tipc_bcast_toggle_rcast(peer->net,
771 				(tn->capabilities & TIPC_BCAST_RCAST));
772 	spin_unlock_bh(&tn->node_list_lock);
773 	return deleted;
774 }
775 
776 /* tipc_node_timeout - handle expiration of node timer
777  */
778 static void tipc_node_timeout(struct timer_list *t)
779 {
780 	struct tipc_node *n = from_timer(n, t, timer);
781 	struct tipc_link_entry *le;
782 	struct sk_buff_head xmitq;
783 	int remains = n->link_cnt;
784 	int bearer_id;
785 	int rc = 0;
786 
787 	trace_tipc_node_timeout(n, false, " ");
788 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
789 		/*Removing the reference of Timer*/
790 		tipc_node_put(n);
791 		return;
792 	}
793 
794 #ifdef CONFIG_TIPC_CRYPTO
795 	/* Take any crypto key related actions first */
796 	tipc_crypto_timeout(n->crypto_rx);
797 #endif
798 	__skb_queue_head_init(&xmitq);
799 
800 	/* Initial node interval to value larger (10 seconds), then it will be
801 	 * recalculated with link lowest tolerance
802 	 */
803 	tipc_node_read_lock(n);
804 	n->keepalive_intv = 10000;
805 	tipc_node_read_unlock(n);
806 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
807 		tipc_node_read_lock(n);
808 		le = &n->links[bearer_id];
809 		if (le->link) {
810 			spin_lock_bh(&le->lock);
811 			/* Link tolerance may change asynchronously: */
812 			tipc_node_calculate_timer(n, le->link);
813 			rc = tipc_link_timeout(le->link, &xmitq);
814 			spin_unlock_bh(&le->lock);
815 			remains--;
816 		}
817 		tipc_node_read_unlock(n);
818 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
819 		if (rc & TIPC_LINK_DOWN_EVT)
820 			tipc_node_link_down(n, bearer_id, false);
821 	}
822 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
823 }
824 
825 /**
826  * __tipc_node_link_up - handle addition of link
827  * @n: target tipc_node
828  * @bearer_id: id of the bearer
829  * @xmitq: queue for messages to be xmited on
830  * Node lock must be held by caller
831  * Link becomes active (alone or shared) or standby, depending on its priority.
832  */
833 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
834 				struct sk_buff_head *xmitq)
835 {
836 	int *slot0 = &n->active_links[0];
837 	int *slot1 = &n->active_links[1];
838 	struct tipc_link *ol = node_active_link(n, 0);
839 	struct tipc_link *nl = n->links[bearer_id].link;
840 
841 	if (!nl || tipc_link_is_up(nl))
842 		return;
843 
844 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
845 	if (!tipc_link_is_up(nl))
846 		return;
847 
848 	n->working_links++;
849 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
850 	n->link_id = tipc_link_id(nl);
851 
852 	/* Leave room for tunnel header when returning 'mtu' to users: */
853 	n->links[bearer_id].mtu = tipc_link_mss(nl);
854 
855 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
856 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
857 
858 	pr_debug("Established link <%s> on network plane %c\n",
859 		 tipc_link_name(nl), tipc_link_plane(nl));
860 	trace_tipc_node_link_up(n, true, " ");
861 
862 	/* Ensure that a STATE message goes first */
863 	tipc_link_build_state_msg(nl, xmitq);
864 
865 	/* First link? => give it both slots */
866 	if (!ol) {
867 		*slot0 = bearer_id;
868 		*slot1 = bearer_id;
869 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
870 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
871 		tipc_link_set_active(nl, true);
872 		tipc_bcast_add_peer(n->net, nl, xmitq);
873 		return;
874 	}
875 
876 	/* Second link => redistribute slots */
877 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
878 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
879 		*slot0 = bearer_id;
880 		*slot1 = bearer_id;
881 		tipc_link_set_active(nl, true);
882 		tipc_link_set_active(ol, false);
883 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
884 		tipc_link_set_active(nl, true);
885 		*slot1 = bearer_id;
886 	} else {
887 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
888 	}
889 
890 	/* Prepare synchronization with first link */
891 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
892 }
893 
894 /**
895  * tipc_node_link_up - handle addition of link
896  * @n: target tipc_node
897  * @bearer_id: id of the bearer
898  * @xmitq: queue for messages to be xmited on
899  *
900  * Link becomes active (alone or shared) or standby, depending on its priority.
901  */
902 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
903 			      struct sk_buff_head *xmitq)
904 {
905 	struct tipc_media_addr *maddr;
906 
907 	tipc_node_write_lock(n);
908 	__tipc_node_link_up(n, bearer_id, xmitq);
909 	maddr = &n->links[bearer_id].maddr;
910 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
911 	tipc_node_write_unlock(n);
912 }
913 
914 /**
915  * tipc_node_link_failover() - start failover in case "half-failover"
916  *
917  * This function is only called in a very special situation where link
918  * failover can be already started on peer node but not on this node.
919  * This can happen when e.g.::
920  *
921  *	1. Both links <1A-2A>, <1B-2B> down
922  *	2. Link endpoint 2A up, but 1A still down (e.g. due to network
923  *	disturbance, wrong session, etc.)
924  *	3. Link <1B-2B> up
925  *	4. Link endpoint 2A down (e.g. due to link tolerance timeout)
926  *	5. Node 2 starts failover onto link <1B-2B>
927  *
928  *	==> Node 1 does never start link/node failover!
929  *
930  * @n: tipc node structure
931  * @l: link peer endpoint failingover (- can be NULL)
932  * @tnl: tunnel link
933  * @xmitq: queue for messages to be xmited on tnl link later
934  */
935 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
936 				    struct tipc_link *tnl,
937 				    struct sk_buff_head *xmitq)
938 {
939 	/* Avoid to be "self-failover" that can never end */
940 	if (!tipc_link_is_up(tnl))
941 		return;
942 
943 	/* Don't rush, failure link may be in the process of resetting */
944 	if (l && !tipc_link_is_reset(l))
945 		return;
946 
947 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
948 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
949 
950 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
951 	tipc_link_failover_prepare(l, tnl, xmitq);
952 
953 	if (l)
954 		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
955 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
956 }
957 
958 /**
959  * __tipc_node_link_down - handle loss of link
960  * @n: target tipc_node
961  * @bearer_id: id of the bearer
962  * @xmitq: queue for messages to be xmited on
963  * @maddr: output media address of the bearer
964  */
965 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
966 				  struct sk_buff_head *xmitq,
967 				  struct tipc_media_addr **maddr)
968 {
969 	struct tipc_link_entry *le = &n->links[*bearer_id];
970 	int *slot0 = &n->active_links[0];
971 	int *slot1 = &n->active_links[1];
972 	int i, highest = 0, prio;
973 	struct tipc_link *l, *_l, *tnl;
974 
975 	l = n->links[*bearer_id].link;
976 	if (!l || tipc_link_is_reset(l))
977 		return;
978 
979 	n->working_links--;
980 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
981 	n->link_id = tipc_link_id(l);
982 
983 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
984 
985 	pr_debug("Lost link <%s> on network plane %c\n",
986 		 tipc_link_name(l), tipc_link_plane(l));
987 
988 	/* Select new active link if any available */
989 	*slot0 = INVALID_BEARER_ID;
990 	*slot1 = INVALID_BEARER_ID;
991 	for (i = 0; i < MAX_BEARERS; i++) {
992 		_l = n->links[i].link;
993 		if (!_l || !tipc_link_is_up(_l))
994 			continue;
995 		if (_l == l)
996 			continue;
997 		prio = tipc_link_prio(_l);
998 		if (prio < highest)
999 			continue;
1000 		if (prio > highest) {
1001 			highest = prio;
1002 			*slot0 = i;
1003 			*slot1 = i;
1004 			continue;
1005 		}
1006 		*slot1 = i;
1007 	}
1008 
1009 	if (!node_is_up(n)) {
1010 		if (tipc_link_peer_is_down(l))
1011 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1012 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1013 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1014 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1015 		tipc_link_reset(l);
1016 		tipc_link_build_reset_msg(l, xmitq);
1017 		*maddr = &n->links[*bearer_id].maddr;
1018 		node_lost_contact(n, &le->inputq);
1019 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1020 		return;
1021 	}
1022 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1023 
1024 	/* There is still a working link => initiate failover */
1025 	*bearer_id = n->active_links[0];
1026 	tnl = n->links[*bearer_id].link;
1027 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1028 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1029 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1030 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1031 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1032 	tipc_link_reset(l);
1033 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
1034 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1035 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1036 	*maddr = &n->links[*bearer_id].maddr;
1037 }
1038 
1039 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1040 {
1041 	struct tipc_link_entry *le = &n->links[bearer_id];
1042 	struct tipc_media_addr *maddr = NULL;
1043 	struct tipc_link *l = le->link;
1044 	int old_bearer_id = bearer_id;
1045 	struct sk_buff_head xmitq;
1046 
1047 	if (!l)
1048 		return;
1049 
1050 	__skb_queue_head_init(&xmitq);
1051 
1052 	tipc_node_write_lock(n);
1053 	if (!tipc_link_is_establishing(l)) {
1054 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1055 	} else {
1056 		/* Defuse pending tipc_node_link_up() */
1057 		tipc_link_reset(l);
1058 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1059 	}
1060 	if (delete) {
1061 		kfree(l);
1062 		le->link = NULL;
1063 		n->link_cnt--;
1064 	}
1065 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
1066 	tipc_node_write_unlock(n);
1067 	if (delete)
1068 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1069 	if (!skb_queue_empty(&xmitq))
1070 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1071 	tipc_sk_rcv(n->net, &le->inputq);
1072 }
1073 
1074 static bool node_is_up(struct tipc_node *n)
1075 {
1076 	return n->active_links[0] != INVALID_BEARER_ID;
1077 }
1078 
1079 bool tipc_node_is_up(struct net *net, u32 addr)
1080 {
1081 	struct tipc_node *n;
1082 	bool retval = false;
1083 
1084 	if (in_own_node(net, addr))
1085 		return true;
1086 
1087 	n = tipc_node_find(net, addr);
1088 	if (!n)
1089 		return false;
1090 	retval = node_is_up(n);
1091 	tipc_node_put(n);
1092 	return retval;
1093 }
1094 
1095 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1096 {
1097 	struct tipc_node *n;
1098 
1099 	addr ^= tipc_net(net)->random;
1100 	while ((n = tipc_node_find(net, addr))) {
1101 		tipc_node_put(n);
1102 		addr++;
1103 	}
1104 	return addr;
1105 }
1106 
1107 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1108  * Returns suggested address if any, otherwise 0
1109  */
1110 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1111 {
1112 	struct tipc_net *tn = tipc_net(net);
1113 	struct tipc_node *n;
1114 	bool preliminary;
1115 	u32 sugg_addr;
1116 
1117 	/* Suggest new address if some other peer is using this one */
1118 	n = tipc_node_find(net, addr);
1119 	if (n) {
1120 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1121 			addr = 0;
1122 		tipc_node_put(n);
1123 		if (!addr)
1124 			return 0;
1125 		return tipc_node_suggest_addr(net, addr);
1126 	}
1127 
1128 	/* Suggest previously used address if peer is known */
1129 	n = tipc_node_find_by_id(net, id);
1130 	if (n) {
1131 		sugg_addr = n->addr;
1132 		preliminary = n->preliminary;
1133 		tipc_node_put(n);
1134 		if (!preliminary)
1135 			return sugg_addr;
1136 	}
1137 
1138 	/* Even this node may be in conflict */
1139 	if (tn->trial_addr == addr)
1140 		return tipc_node_suggest_addr(net, addr);
1141 
1142 	return 0;
1143 }
1144 
1145 void tipc_node_check_dest(struct net *net, u32 addr,
1146 			  u8 *peer_id, struct tipc_bearer *b,
1147 			  u16 capabilities, u32 signature, u32 hash_mixes,
1148 			  struct tipc_media_addr *maddr,
1149 			  bool *respond, bool *dupl_addr)
1150 {
1151 	struct tipc_node *n;
1152 	struct tipc_link *l, *snd_l;
1153 	struct tipc_link_entry *le;
1154 	bool addr_match = false;
1155 	bool sign_match = false;
1156 	bool link_up = false;
1157 	bool accept_addr = false;
1158 	bool reset = true;
1159 	char *if_name;
1160 	unsigned long intv;
1161 	u16 session;
1162 
1163 	*dupl_addr = false;
1164 	*respond = false;
1165 
1166 	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1167 			     false);
1168 	if (!n)
1169 		return;
1170 
1171 	tipc_node_write_lock(n);
1172 	if (unlikely(!n->bc_entry.link)) {
1173 		snd_l = tipc_bc_sndlink(net);
1174 		if (!tipc_link_bc_create(net, tipc_own_addr(net),
1175 					 addr, peer_id, U16_MAX,
1176 					 tipc_link_min_win(snd_l),
1177 					 tipc_link_max_win(snd_l),
1178 					 n->capabilities,
1179 					 &n->bc_entry.inputq1,
1180 					 &n->bc_entry.namedq, snd_l,
1181 					 &n->bc_entry.link)) {
1182 			pr_warn("Broadcast rcv link creation failed, no mem\n");
1183 			tipc_node_write_unlock_fast(n);
1184 			tipc_node_put(n);
1185 			return;
1186 		}
1187 	}
1188 
1189 	le = &n->links[b->identity];
1190 
1191 	/* Prepare to validate requesting node's signature and media address */
1192 	l = le->link;
1193 	link_up = l && tipc_link_is_up(l);
1194 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1195 	sign_match = (signature == n->signature);
1196 
1197 	/* These three flags give us eight permutations: */
1198 
1199 	if (sign_match && addr_match && link_up) {
1200 		/* All is fine. Do nothing. */
1201 		reset = false;
1202 		/* Peer node is not a container/local namespace */
1203 		if (!n->peer_hash_mix)
1204 			n->peer_hash_mix = hash_mixes;
1205 	} else if (sign_match && addr_match && !link_up) {
1206 		/* Respond. The link will come up in due time */
1207 		*respond = true;
1208 	} else if (sign_match && !addr_match && link_up) {
1209 		/* Peer has changed i/f address without rebooting.
1210 		 * If so, the link will reset soon, and the next
1211 		 * discovery will be accepted. So we can ignore it.
1212 		 * It may also be an cloned or malicious peer having
1213 		 * chosen the same node address and signature as an
1214 		 * existing one.
1215 		 * Ignore requests until the link goes down, if ever.
1216 		 */
1217 		*dupl_addr = true;
1218 	} else if (sign_match && !addr_match && !link_up) {
1219 		/* Peer link has changed i/f address without rebooting.
1220 		 * It may also be a cloned or malicious peer; we can't
1221 		 * distinguish between the two.
1222 		 * The signature is correct, so we must accept.
1223 		 */
1224 		accept_addr = true;
1225 		*respond = true;
1226 	} else if (!sign_match && addr_match && link_up) {
1227 		/* Peer node rebooted. Two possibilities:
1228 		 *  - Delayed re-discovery; this link endpoint has already
1229 		 *    reset and re-established contact with the peer, before
1230 		 *    receiving a discovery message from that node.
1231 		 *    (The peer happened to receive one from this node first).
1232 		 *  - The peer came back so fast that our side has not
1233 		 *    discovered it yet. Probing from this side will soon
1234 		 *    reset the link, since there can be no working link
1235 		 *    endpoint at the peer end, and the link will re-establish.
1236 		 *  Accept the signature, since it comes from a known peer.
1237 		 */
1238 		n->signature = signature;
1239 	} else if (!sign_match && addr_match && !link_up) {
1240 		/*  The peer node has rebooted.
1241 		 *  Accept signature, since it is a known peer.
1242 		 */
1243 		n->signature = signature;
1244 		*respond = true;
1245 	} else if (!sign_match && !addr_match && link_up) {
1246 		/* Peer rebooted with new address, or a new/duplicate peer.
1247 		 * Ignore until the link goes down, if ever.
1248 		 */
1249 		*dupl_addr = true;
1250 	} else if (!sign_match && !addr_match && !link_up) {
1251 		/* Peer rebooted with new address, or it is a new peer.
1252 		 * Accept signature and address.
1253 		 */
1254 		n->signature = signature;
1255 		accept_addr = true;
1256 		*respond = true;
1257 	}
1258 
1259 	if (!accept_addr)
1260 		goto exit;
1261 
1262 	/* Now create new link if not already existing */
1263 	if (!l) {
1264 		if (n->link_cnt == 2)
1265 			goto exit;
1266 
1267 		if_name = strchr(b->name, ':') + 1;
1268 		get_random_bytes(&session, sizeof(u16));
1269 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1270 				      b->net_plane, b->mtu, b->priority,
1271 				      b->min_win, b->max_win, session,
1272 				      tipc_own_addr(net), addr, peer_id,
1273 				      n->capabilities,
1274 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1275 				      &le->inputq,
1276 				      &n->bc_entry.namedq, &l)) {
1277 			*respond = false;
1278 			goto exit;
1279 		}
1280 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1281 		tipc_link_reset(l);
1282 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1283 		if (n->state == NODE_FAILINGOVER)
1284 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1285 		le->link = l;
1286 		n->link_cnt++;
1287 		tipc_node_calculate_timer(n, l);
1288 		if (n->link_cnt == 1) {
1289 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1290 			if (!mod_timer(&n->timer, intv))
1291 				tipc_node_get(n);
1292 		}
1293 	}
1294 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1295 exit:
1296 	tipc_node_write_unlock(n);
1297 	if (reset && l && !tipc_link_is_reset(l))
1298 		tipc_node_link_down(n, b->identity, false);
1299 	tipc_node_put(n);
1300 }
1301 
1302 void tipc_node_delete_links(struct net *net, int bearer_id)
1303 {
1304 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1305 	struct tipc_node *n;
1306 
1307 	rcu_read_lock();
1308 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1309 		tipc_node_link_down(n, bearer_id, true);
1310 	}
1311 	rcu_read_unlock();
1312 }
1313 
1314 static void tipc_node_reset_links(struct tipc_node *n)
1315 {
1316 	int i;
1317 
1318 	pr_warn("Resetting all links to %x\n", n->addr);
1319 
1320 	trace_tipc_node_reset_links(n, true, " ");
1321 	for (i = 0; i < MAX_BEARERS; i++) {
1322 		tipc_node_link_down(n, i, false);
1323 	}
1324 }
1325 
1326 /* tipc_node_fsm_evt - node finite state machine
1327  * Determines when contact is allowed with peer node
1328  */
1329 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1330 {
1331 	int state = n->state;
1332 
1333 	switch (state) {
1334 	case SELF_DOWN_PEER_DOWN:
1335 		switch (evt) {
1336 		case SELF_ESTABL_CONTACT_EVT:
1337 			state = SELF_UP_PEER_COMING;
1338 			break;
1339 		case PEER_ESTABL_CONTACT_EVT:
1340 			state = SELF_COMING_PEER_UP;
1341 			break;
1342 		case SELF_LOST_CONTACT_EVT:
1343 		case PEER_LOST_CONTACT_EVT:
1344 			break;
1345 		case NODE_SYNCH_END_EVT:
1346 		case NODE_SYNCH_BEGIN_EVT:
1347 		case NODE_FAILOVER_BEGIN_EVT:
1348 		case NODE_FAILOVER_END_EVT:
1349 		default:
1350 			goto illegal_evt;
1351 		}
1352 		break;
1353 	case SELF_UP_PEER_UP:
1354 		switch (evt) {
1355 		case SELF_LOST_CONTACT_EVT:
1356 			state = SELF_DOWN_PEER_LEAVING;
1357 			break;
1358 		case PEER_LOST_CONTACT_EVT:
1359 			state = SELF_LEAVING_PEER_DOWN;
1360 			break;
1361 		case NODE_SYNCH_BEGIN_EVT:
1362 			state = NODE_SYNCHING;
1363 			break;
1364 		case NODE_FAILOVER_BEGIN_EVT:
1365 			state = NODE_FAILINGOVER;
1366 			break;
1367 		case SELF_ESTABL_CONTACT_EVT:
1368 		case PEER_ESTABL_CONTACT_EVT:
1369 		case NODE_SYNCH_END_EVT:
1370 		case NODE_FAILOVER_END_EVT:
1371 			break;
1372 		default:
1373 			goto illegal_evt;
1374 		}
1375 		break;
1376 	case SELF_DOWN_PEER_LEAVING:
1377 		switch (evt) {
1378 		case PEER_LOST_CONTACT_EVT:
1379 			state = SELF_DOWN_PEER_DOWN;
1380 			break;
1381 		case SELF_ESTABL_CONTACT_EVT:
1382 		case PEER_ESTABL_CONTACT_EVT:
1383 		case SELF_LOST_CONTACT_EVT:
1384 			break;
1385 		case NODE_SYNCH_END_EVT:
1386 		case NODE_SYNCH_BEGIN_EVT:
1387 		case NODE_FAILOVER_BEGIN_EVT:
1388 		case NODE_FAILOVER_END_EVT:
1389 		default:
1390 			goto illegal_evt;
1391 		}
1392 		break;
1393 	case SELF_UP_PEER_COMING:
1394 		switch (evt) {
1395 		case PEER_ESTABL_CONTACT_EVT:
1396 			state = SELF_UP_PEER_UP;
1397 			break;
1398 		case SELF_LOST_CONTACT_EVT:
1399 			state = SELF_DOWN_PEER_DOWN;
1400 			break;
1401 		case SELF_ESTABL_CONTACT_EVT:
1402 		case PEER_LOST_CONTACT_EVT:
1403 		case NODE_SYNCH_END_EVT:
1404 		case NODE_FAILOVER_BEGIN_EVT:
1405 			break;
1406 		case NODE_SYNCH_BEGIN_EVT:
1407 		case NODE_FAILOVER_END_EVT:
1408 		default:
1409 			goto illegal_evt;
1410 		}
1411 		break;
1412 	case SELF_COMING_PEER_UP:
1413 		switch (evt) {
1414 		case SELF_ESTABL_CONTACT_EVT:
1415 			state = SELF_UP_PEER_UP;
1416 			break;
1417 		case PEER_LOST_CONTACT_EVT:
1418 			state = SELF_DOWN_PEER_DOWN;
1419 			break;
1420 		case SELF_LOST_CONTACT_EVT:
1421 		case PEER_ESTABL_CONTACT_EVT:
1422 			break;
1423 		case NODE_SYNCH_END_EVT:
1424 		case NODE_SYNCH_BEGIN_EVT:
1425 		case NODE_FAILOVER_BEGIN_EVT:
1426 		case NODE_FAILOVER_END_EVT:
1427 		default:
1428 			goto illegal_evt;
1429 		}
1430 		break;
1431 	case SELF_LEAVING_PEER_DOWN:
1432 		switch (evt) {
1433 		case SELF_LOST_CONTACT_EVT:
1434 			state = SELF_DOWN_PEER_DOWN;
1435 			break;
1436 		case SELF_ESTABL_CONTACT_EVT:
1437 		case PEER_ESTABL_CONTACT_EVT:
1438 		case PEER_LOST_CONTACT_EVT:
1439 			break;
1440 		case NODE_SYNCH_END_EVT:
1441 		case NODE_SYNCH_BEGIN_EVT:
1442 		case NODE_FAILOVER_BEGIN_EVT:
1443 		case NODE_FAILOVER_END_EVT:
1444 		default:
1445 			goto illegal_evt;
1446 		}
1447 		break;
1448 	case NODE_FAILINGOVER:
1449 		switch (evt) {
1450 		case SELF_LOST_CONTACT_EVT:
1451 			state = SELF_DOWN_PEER_LEAVING;
1452 			break;
1453 		case PEER_LOST_CONTACT_EVT:
1454 			state = SELF_LEAVING_PEER_DOWN;
1455 			break;
1456 		case NODE_FAILOVER_END_EVT:
1457 			state = SELF_UP_PEER_UP;
1458 			break;
1459 		case NODE_FAILOVER_BEGIN_EVT:
1460 		case SELF_ESTABL_CONTACT_EVT:
1461 		case PEER_ESTABL_CONTACT_EVT:
1462 			break;
1463 		case NODE_SYNCH_BEGIN_EVT:
1464 		case NODE_SYNCH_END_EVT:
1465 		default:
1466 			goto illegal_evt;
1467 		}
1468 		break;
1469 	case NODE_SYNCHING:
1470 		switch (evt) {
1471 		case SELF_LOST_CONTACT_EVT:
1472 			state = SELF_DOWN_PEER_LEAVING;
1473 			break;
1474 		case PEER_LOST_CONTACT_EVT:
1475 			state = SELF_LEAVING_PEER_DOWN;
1476 			break;
1477 		case NODE_SYNCH_END_EVT:
1478 			state = SELF_UP_PEER_UP;
1479 			break;
1480 		case NODE_FAILOVER_BEGIN_EVT:
1481 			state = NODE_FAILINGOVER;
1482 			break;
1483 		case NODE_SYNCH_BEGIN_EVT:
1484 		case SELF_ESTABL_CONTACT_EVT:
1485 		case PEER_ESTABL_CONTACT_EVT:
1486 			break;
1487 		case NODE_FAILOVER_END_EVT:
1488 		default:
1489 			goto illegal_evt;
1490 		}
1491 		break;
1492 	default:
1493 		pr_err("Unknown node fsm state %x\n", state);
1494 		break;
1495 	}
1496 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1497 	n->state = state;
1498 	return;
1499 
1500 illegal_evt:
1501 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1502 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1503 }
1504 
1505 static void node_lost_contact(struct tipc_node *n,
1506 			      struct sk_buff_head *inputq)
1507 {
1508 	struct tipc_sock_conn *conn, *safe;
1509 	struct tipc_link *l;
1510 	struct list_head *conns = &n->conn_sks;
1511 	struct sk_buff *skb;
1512 	uint i;
1513 
1514 	pr_debug("Lost contact with %x\n", n->addr);
1515 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1516 	trace_tipc_node_lost_contact(n, true, " ");
1517 
1518 	/* Clean up broadcast state */
1519 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1520 	skb_queue_purge(&n->bc_entry.namedq);
1521 
1522 	/* Abort any ongoing link failover */
1523 	for (i = 0; i < MAX_BEARERS; i++) {
1524 		l = n->links[i].link;
1525 		if (l)
1526 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1527 	}
1528 
1529 	/* Notify publications from this node */
1530 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1531 	n->peer_net = NULL;
1532 	n->peer_hash_mix = 0;
1533 	/* Notify sockets connected to node */
1534 	list_for_each_entry_safe(conn, safe, conns, list) {
1535 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1536 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1537 				      conn->peer_node, conn->port,
1538 				      conn->peer_port, TIPC_ERR_NO_NODE);
1539 		if (likely(skb))
1540 			skb_queue_tail(inputq, skb);
1541 		list_del(&conn->list);
1542 		kfree(conn);
1543 	}
1544 }
1545 
1546 /**
1547  * tipc_node_get_linkname - get the name of a link
1548  *
1549  * @net: the applicable net namespace
1550  * @bearer_id: id of the bearer
1551  * @addr: peer node address
1552  * @linkname: link name output buffer
1553  * @len: size of @linkname output buffer
1554  *
1555  * Return: 0 on success
1556  */
1557 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1558 			   char *linkname, size_t len)
1559 {
1560 	struct tipc_link *link;
1561 	int err = -EINVAL;
1562 	struct tipc_node *node = tipc_node_find(net, addr);
1563 
1564 	if (!node)
1565 		return err;
1566 
1567 	if (bearer_id >= MAX_BEARERS)
1568 		goto exit;
1569 
1570 	tipc_node_read_lock(node);
1571 	link = node->links[bearer_id].link;
1572 	if (link) {
1573 		strncpy(linkname, tipc_link_name(link), len);
1574 		err = 0;
1575 	}
1576 	tipc_node_read_unlock(node);
1577 exit:
1578 	tipc_node_put(node);
1579 	return err;
1580 }
1581 
1582 /* Caller should hold node lock for the passed node */
1583 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1584 {
1585 	void *hdr;
1586 	struct nlattr *attrs;
1587 
1588 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1589 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1590 	if (!hdr)
1591 		return -EMSGSIZE;
1592 
1593 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1594 	if (!attrs)
1595 		goto msg_full;
1596 
1597 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1598 		goto attr_msg_full;
1599 	if (node_is_up(node))
1600 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1601 			goto attr_msg_full;
1602 
1603 	nla_nest_end(msg->skb, attrs);
1604 	genlmsg_end(msg->skb, hdr);
1605 
1606 	return 0;
1607 
1608 attr_msg_full:
1609 	nla_nest_cancel(msg->skb, attrs);
1610 msg_full:
1611 	genlmsg_cancel(msg->skb, hdr);
1612 
1613 	return -EMSGSIZE;
1614 }
1615 
1616 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1617 {
1618 	struct tipc_msg *hdr = buf_msg(skb_peek(list));
1619 	struct sk_buff_head inputq;
1620 
1621 	switch (msg_user(hdr)) {
1622 	case TIPC_LOW_IMPORTANCE:
1623 	case TIPC_MEDIUM_IMPORTANCE:
1624 	case TIPC_HIGH_IMPORTANCE:
1625 	case TIPC_CRITICAL_IMPORTANCE:
1626 		if (msg_connected(hdr) || msg_named(hdr) ||
1627 		    msg_direct(hdr)) {
1628 			tipc_loopback_trace(peer_net, list);
1629 			spin_lock_init(&list->lock);
1630 			tipc_sk_rcv(peer_net, list);
1631 			return;
1632 		}
1633 		if (msg_mcast(hdr)) {
1634 			tipc_loopback_trace(peer_net, list);
1635 			skb_queue_head_init(&inputq);
1636 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1637 			__skb_queue_purge(list);
1638 			skb_queue_purge(&inputq);
1639 			return;
1640 		}
1641 		return;
1642 	case MSG_FRAGMENTER:
1643 		if (tipc_msg_assemble(list)) {
1644 			tipc_loopback_trace(peer_net, list);
1645 			skb_queue_head_init(&inputq);
1646 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1647 			__skb_queue_purge(list);
1648 			skb_queue_purge(&inputq);
1649 		}
1650 		return;
1651 	case GROUP_PROTOCOL:
1652 	case CONN_MANAGER:
1653 		tipc_loopback_trace(peer_net, list);
1654 		spin_lock_init(&list->lock);
1655 		tipc_sk_rcv(peer_net, list);
1656 		return;
1657 	case LINK_PROTOCOL:
1658 	case NAME_DISTRIBUTOR:
1659 	case TUNNEL_PROTOCOL:
1660 	case BCAST_PROTOCOL:
1661 		return;
1662 	default:
1663 		return;
1664 	}
1665 }
1666 
1667 /**
1668  * tipc_node_xmit() - general link level function for message sending
1669  * @net: the applicable net namespace
1670  * @list: chain of buffers containing message
1671  * @dnode: address of destination node
1672  * @selector: a number used for deterministic link selection
1673  * Consumes the buffer chain.
1674  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1675  */
1676 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1677 		   u32 dnode, int selector)
1678 {
1679 	struct tipc_link_entry *le = NULL;
1680 	struct tipc_node *n;
1681 	struct sk_buff_head xmitq;
1682 	bool node_up = false;
1683 	int bearer_id;
1684 	int rc;
1685 
1686 	if (in_own_node(net, dnode)) {
1687 		tipc_loopback_trace(net, list);
1688 		spin_lock_init(&list->lock);
1689 		tipc_sk_rcv(net, list);
1690 		return 0;
1691 	}
1692 
1693 	n = tipc_node_find(net, dnode);
1694 	if (unlikely(!n)) {
1695 		__skb_queue_purge(list);
1696 		return -EHOSTUNREACH;
1697 	}
1698 
1699 	tipc_node_read_lock(n);
1700 	node_up = node_is_up(n);
1701 	if (node_up && n->peer_net && check_net(n->peer_net)) {
1702 		/* xmit inner linux container */
1703 		tipc_lxc_xmit(n->peer_net, list);
1704 		if (likely(skb_queue_empty(list))) {
1705 			tipc_node_read_unlock(n);
1706 			tipc_node_put(n);
1707 			return 0;
1708 		}
1709 	}
1710 
1711 	bearer_id = n->active_links[selector & 1];
1712 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1713 		tipc_node_read_unlock(n);
1714 		tipc_node_put(n);
1715 		__skb_queue_purge(list);
1716 		return -EHOSTUNREACH;
1717 	}
1718 
1719 	__skb_queue_head_init(&xmitq);
1720 	le = &n->links[bearer_id];
1721 	spin_lock_bh(&le->lock);
1722 	rc = tipc_link_xmit(le->link, list, &xmitq);
1723 	spin_unlock_bh(&le->lock);
1724 	tipc_node_read_unlock(n);
1725 
1726 	if (unlikely(rc == -ENOBUFS))
1727 		tipc_node_link_down(n, bearer_id, false);
1728 	else
1729 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1730 
1731 	tipc_node_put(n);
1732 
1733 	return rc;
1734 }
1735 
1736 /* tipc_node_xmit_skb(): send single buffer to destination
1737  * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE
1738  * messages, which will not be rejected
1739  * The only exception is datagram messages rerouted after secondary
1740  * lookup, which are rare and safe to dispose of anyway.
1741  */
1742 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1743 		       u32 selector)
1744 {
1745 	struct sk_buff_head head;
1746 
1747 	__skb_queue_head_init(&head);
1748 	__skb_queue_tail(&head, skb);
1749 	tipc_node_xmit(net, &head, dnode, selector);
1750 	return 0;
1751 }
1752 
1753 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1754  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1755  */
1756 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1757 {
1758 	struct sk_buff *skb;
1759 	u32 selector, dnode;
1760 
1761 	while ((skb = __skb_dequeue(xmitq))) {
1762 		selector = msg_origport(buf_msg(skb));
1763 		dnode = msg_destnode(buf_msg(skb));
1764 		tipc_node_xmit_skb(net, skb, dnode, selector);
1765 	}
1766 	return 0;
1767 }
1768 
1769 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1770 {
1771 	struct sk_buff_head xmitq;
1772 	struct sk_buff *txskb;
1773 	struct tipc_node *n;
1774 	u16 dummy;
1775 	u32 dst;
1776 
1777 	/* Use broadcast if all nodes support it */
1778 	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1779 		__skb_queue_head_init(&xmitq);
1780 		__skb_queue_tail(&xmitq, skb);
1781 		tipc_bcast_xmit(net, &xmitq, &dummy);
1782 		return;
1783 	}
1784 
1785 	/* Otherwise use legacy replicast method */
1786 	rcu_read_lock();
1787 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1788 		dst = n->addr;
1789 		if (in_own_node(net, dst))
1790 			continue;
1791 		if (!node_is_up(n))
1792 			continue;
1793 		txskb = pskb_copy(skb, GFP_ATOMIC);
1794 		if (!txskb)
1795 			break;
1796 		msg_set_destnode(buf_msg(txskb), dst);
1797 		tipc_node_xmit_skb(net, txskb, dst, 0);
1798 	}
1799 	rcu_read_unlock();
1800 	kfree_skb(skb);
1801 }
1802 
1803 static void tipc_node_mcast_rcv(struct tipc_node *n)
1804 {
1805 	struct tipc_bclink_entry *be = &n->bc_entry;
1806 
1807 	/* 'arrvq' is under inputq2's lock protection */
1808 	spin_lock_bh(&be->inputq2.lock);
1809 	spin_lock_bh(&be->inputq1.lock);
1810 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1811 	spin_unlock_bh(&be->inputq1.lock);
1812 	spin_unlock_bh(&be->inputq2.lock);
1813 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1814 }
1815 
1816 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1817 				  int bearer_id, struct sk_buff_head *xmitq)
1818 {
1819 	struct tipc_link *ucl;
1820 	int rc;
1821 
1822 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);
1823 
1824 	if (rc & TIPC_LINK_DOWN_EVT) {
1825 		tipc_node_reset_links(n);
1826 		return;
1827 	}
1828 
1829 	if (!(rc & TIPC_LINK_SND_STATE))
1830 		return;
1831 
1832 	/* If probe message, a STATE response will be sent anyway */
1833 	if (msg_probe(hdr))
1834 		return;
1835 
1836 	/* Produce a STATE message carrying broadcast NACK */
1837 	tipc_node_read_lock(n);
1838 	ucl = n->links[bearer_id].link;
1839 	if (ucl)
1840 		tipc_link_build_state_msg(ucl, xmitq);
1841 	tipc_node_read_unlock(n);
1842 }
1843 
1844 /**
1845  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1846  * @net: the applicable net namespace
1847  * @skb: TIPC packet
1848  * @bearer_id: id of bearer message arrived on
1849  *
1850  * Invoked with no locks held.
1851  */
1852 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1853 {
1854 	int rc;
1855 	struct sk_buff_head xmitq;
1856 	struct tipc_bclink_entry *be;
1857 	struct tipc_link_entry *le;
1858 	struct tipc_msg *hdr = buf_msg(skb);
1859 	int usr = msg_user(hdr);
1860 	u32 dnode = msg_destnode(hdr);
1861 	struct tipc_node *n;
1862 
1863 	__skb_queue_head_init(&xmitq);
1864 
1865 	/* If NACK for other node, let rcv link for that node peek into it */
1866 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1867 		n = tipc_node_find(net, dnode);
1868 	else
1869 		n = tipc_node_find(net, msg_prevnode(hdr));
1870 	if (!n) {
1871 		kfree_skb(skb);
1872 		return;
1873 	}
1874 	be = &n->bc_entry;
1875 	le = &n->links[bearer_id];
1876 
1877 	rc = tipc_bcast_rcv(net, be->link, skb);
1878 
1879 	/* Broadcast ACKs are sent on a unicast link */
1880 	if (rc & TIPC_LINK_SND_STATE) {
1881 		tipc_node_read_lock(n);
1882 		tipc_link_build_state_msg(le->link, &xmitq);
1883 		tipc_node_read_unlock(n);
1884 	}
1885 
1886 	if (!skb_queue_empty(&xmitq))
1887 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1888 
1889 	if (!skb_queue_empty(&be->inputq1))
1890 		tipc_node_mcast_rcv(n);
1891 
1892 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1893 	if (!skb_queue_empty(&n->bc_entry.namedq))
1894 		tipc_named_rcv(net, &n->bc_entry.namedq,
1895 			       &n->bc_entry.named_rcv_nxt,
1896 			       &n->bc_entry.named_open);
1897 
1898 	/* If reassembly or retransmission failure => reset all links to peer */
1899 	if (rc & TIPC_LINK_DOWN_EVT)
1900 		tipc_node_reset_links(n);
1901 
1902 	tipc_node_put(n);
1903 }
1904 
1905 /**
1906  * tipc_node_check_state - check and if necessary update node state
1907  * @n: target tipc_node
1908  * @skb: TIPC packet
1909  * @bearer_id: identity of bearer delivering the packet
1910  * @xmitq: queue for messages to be xmited on
1911  * Return: true if state and msg are ok, otherwise false
1912  */
1913 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1914 				  int bearer_id, struct sk_buff_head *xmitq)
1915 {
1916 	struct tipc_msg *hdr = buf_msg(skb);
1917 	int usr = msg_user(hdr);
1918 	int mtyp = msg_type(hdr);
1919 	u16 oseqno = msg_seqno(hdr);
1920 	u16 exp_pkts = msg_msgcnt(hdr);
1921 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1922 	int state = n->state;
1923 	struct tipc_link *l, *tnl, *pl = NULL;
1924 	struct tipc_media_addr *maddr;
1925 	int pb_id;
1926 
1927 	if (trace_tipc_node_check_state_enabled()) {
1928 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1929 		trace_tipc_node_check_state(n, true, " ");
1930 	}
1931 	l = n->links[bearer_id].link;
1932 	if (!l)
1933 		return false;
1934 	rcv_nxt = tipc_link_rcv_nxt(l);
1935 
1936 
1937 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1938 		return true;
1939 
1940 	/* Find parallel link, if any */
1941 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1942 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1943 			pl = n->links[pb_id].link;
1944 			break;
1945 		}
1946 	}
1947 
1948 	if (!tipc_link_validate_msg(l, hdr)) {
1949 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1950 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1951 		return false;
1952 	}
1953 
1954 	/* Check and update node accesibility if applicable */
1955 	if (state == SELF_UP_PEER_COMING) {
1956 		if (!tipc_link_is_up(l))
1957 			return true;
1958 		if (!msg_peer_link_is_up(hdr))
1959 			return true;
1960 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1961 	}
1962 
1963 	if (state == SELF_DOWN_PEER_LEAVING) {
1964 		if (msg_peer_node_is_up(hdr))
1965 			return false;
1966 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1967 		return true;
1968 	}
1969 
1970 	if (state == SELF_LEAVING_PEER_DOWN)
1971 		return false;
1972 
1973 	/* Ignore duplicate packets */
1974 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1975 		return true;
1976 
1977 	/* Initiate or update failover mode if applicable */
1978 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1979 		syncpt = oseqno + exp_pkts - 1;
1980 		if (pl && !tipc_link_is_reset(pl)) {
1981 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
1982 			trace_tipc_node_link_down(n, true,
1983 						  "node link down <- failover!");
1984 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
1985 							tipc_link_inputq(l));
1986 		}
1987 
1988 		/* If parallel link was already down, and this happened before
1989 		 * the tunnel link came up, node failover was never started.
1990 		 * Ensure that a FAILOVER_MSG is sent to get peer out of
1991 		 * NODE_FAILINGOVER state, also this node must accept
1992 		 * TUNNEL_MSGs from peer.
1993 		 */
1994 		if (n->state != NODE_FAILINGOVER)
1995 			tipc_node_link_failover(n, pl, l, xmitq);
1996 
1997 		/* If pkts arrive out of order, use lowest calculated syncpt */
1998 		if (less(syncpt, n->sync_point))
1999 			n->sync_point = syncpt;
2000 	}
2001 
2002 	/* Open parallel link when tunnel link reaches synch point */
2003 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2004 		if (!more(rcv_nxt, n->sync_point))
2005 			return true;
2006 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2007 		if (pl)
2008 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2009 		return true;
2010 	}
2011 
2012 	/* No synching needed if only one link */
2013 	if (!pl || !tipc_link_is_up(pl))
2014 		return true;
2015 
2016 	/* Initiate synch mode if applicable */
2017 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2018 		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2019 			syncpt = msg_syncpt(hdr);
2020 		else
2021 			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2022 		if (!tipc_link_is_up(l))
2023 			__tipc_node_link_up(n, bearer_id, xmitq);
2024 		if (n->state == SELF_UP_PEER_UP) {
2025 			n->sync_point = syncpt;
2026 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2027 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2028 		}
2029 	}
2030 
2031 	/* Open tunnel link when parallel link reaches synch point */
2032 	if (n->state == NODE_SYNCHING) {
2033 		if (tipc_link_is_synching(l)) {
2034 			tnl = l;
2035 		} else {
2036 			tnl = pl;
2037 			pl = l;
2038 		}
2039 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
2040 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2041 		if (more(dlv_nxt, n->sync_point)) {
2042 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2043 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2044 			return true;
2045 		}
2046 		if (l == pl)
2047 			return true;
2048 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2049 			return true;
2050 		if (usr == LINK_PROTOCOL)
2051 			return true;
2052 		return false;
2053 	}
2054 	return true;
2055 }
2056 
2057 /**
2058  * tipc_rcv - process TIPC packets/messages arriving from off-node
2059  * @net: the applicable net namespace
2060  * @skb: TIPC packet
2061  * @b: pointer to bearer message arrived on
2062  *
2063  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2064  * structure (i.e. cannot be NULL), but bearer can be inactive.
2065  */
2066 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2067 {
2068 	struct sk_buff_head xmitq;
2069 	struct tipc_link_entry *le;
2070 	struct tipc_msg *hdr;
2071 	struct tipc_node *n;
2072 	int bearer_id = b->identity;
2073 	u32 self = tipc_own_addr(net);
2074 	int usr, rc = 0;
2075 	u16 bc_ack;
2076 #ifdef CONFIG_TIPC_CRYPTO
2077 	struct tipc_ehdr *ehdr;
2078 
2079 	/* Check if message must be decrypted first */
2080 	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2081 		goto rcv;
2082 
2083 	ehdr = (struct tipc_ehdr *)skb->data;
2084 	if (likely(ehdr->user != LINK_CONFIG)) {
2085 		n = tipc_node_find(net, ntohl(ehdr->addr));
2086 		if (unlikely(!n))
2087 			goto discard;
2088 	} else {
2089 		n = tipc_node_find_by_id(net, ehdr->id);
2090 	}
2091 	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2092 	if (!skb)
2093 		return;
2094 
2095 rcv:
2096 #endif
2097 	/* Ensure message is well-formed before touching the header */
2098 	if (unlikely(!tipc_msg_validate(&skb)))
2099 		goto discard;
2100 	__skb_queue_head_init(&xmitq);
2101 	hdr = buf_msg(skb);
2102 	usr = msg_user(hdr);
2103 	bc_ack = msg_bcast_ack(hdr);
2104 
2105 	/* Handle arrival of discovery or broadcast packet */
2106 	if (unlikely(msg_non_seq(hdr))) {
2107 		if (unlikely(usr == LINK_CONFIG))
2108 			return tipc_disc_rcv(net, skb, b);
2109 		else
2110 			return tipc_node_bc_rcv(net, skb, bearer_id);
2111 	}
2112 
2113 	/* Discard unicast link messages destined for another node */
2114 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2115 		goto discard;
2116 
2117 	/* Locate neighboring node that sent packet */
2118 	n = tipc_node_find(net, msg_prevnode(hdr));
2119 	if (unlikely(!n))
2120 		goto discard;
2121 	le = &n->links[bearer_id];
2122 
2123 	/* Ensure broadcast reception is in synch with peer's send state */
2124 	if (unlikely(usr == LINK_PROTOCOL)) {
2125 		if (unlikely(skb_linearize(skb))) {
2126 			tipc_node_put(n);
2127 			goto discard;
2128 		}
2129 		hdr = buf_msg(skb);
2130 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
2131 	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2132 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2133 	}
2134 
2135 	/* Receive packet directly if conditions permit */
2136 	tipc_node_read_lock(n);
2137 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2138 		spin_lock_bh(&le->lock);
2139 		if (le->link) {
2140 			rc = tipc_link_rcv(le->link, skb, &xmitq);
2141 			skb = NULL;
2142 		}
2143 		spin_unlock_bh(&le->lock);
2144 	}
2145 	tipc_node_read_unlock(n);
2146 
2147 	/* Check/update node state before receiving */
2148 	if (unlikely(skb)) {
2149 		if (unlikely(skb_linearize(skb)))
2150 			goto out_node_put;
2151 		tipc_node_write_lock(n);
2152 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2153 			if (le->link) {
2154 				rc = tipc_link_rcv(le->link, skb, &xmitq);
2155 				skb = NULL;
2156 			}
2157 		}
2158 		tipc_node_write_unlock(n);
2159 	}
2160 
2161 	if (unlikely(rc & TIPC_LINK_UP_EVT))
2162 		tipc_node_link_up(n, bearer_id, &xmitq);
2163 
2164 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2165 		tipc_node_link_down(n, bearer_id, false);
2166 
2167 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2168 		tipc_named_rcv(net, &n->bc_entry.namedq,
2169 			       &n->bc_entry.named_rcv_nxt,
2170 			       &n->bc_entry.named_open);
2171 
2172 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2173 		tipc_node_mcast_rcv(n);
2174 
2175 	if (!skb_queue_empty(&le->inputq))
2176 		tipc_sk_rcv(net, &le->inputq);
2177 
2178 	if (!skb_queue_empty(&xmitq))
2179 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2180 
2181 out_node_put:
2182 	tipc_node_put(n);
2183 discard:
2184 	kfree_skb(skb);
2185 }
2186 
2187 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2188 			      int prop)
2189 {
2190 	struct tipc_net *tn = tipc_net(net);
2191 	int bearer_id = b->identity;
2192 	struct sk_buff_head xmitq;
2193 	struct tipc_link_entry *e;
2194 	struct tipc_node *n;
2195 
2196 	__skb_queue_head_init(&xmitq);
2197 
2198 	rcu_read_lock();
2199 
2200 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2201 		tipc_node_write_lock(n);
2202 		e = &n->links[bearer_id];
2203 		if (e->link) {
2204 			if (prop == TIPC_NLA_PROP_TOL)
2205 				tipc_link_set_tolerance(e->link, b->tolerance,
2206 							&xmitq);
2207 			else if (prop == TIPC_NLA_PROP_MTU)
2208 				tipc_link_set_mtu(e->link, b->mtu);
2209 
2210 			/* Update MTU for node link entry */
2211 			e->mtu = tipc_link_mss(e->link);
2212 		}
2213 
2214 		tipc_node_write_unlock(n);
2215 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2216 	}
2217 
2218 	rcu_read_unlock();
2219 }
2220 
2221 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2222 {
2223 	struct net *net = sock_net(skb->sk);
2224 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2225 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2226 	struct tipc_node *peer, *temp_node;
2227 	u8 node_id[NODE_ID_LEN];
2228 	u64 *w0 = (u64 *)&node_id[0];
2229 	u64 *w1 = (u64 *)&node_id[8];
2230 	u32 addr;
2231 	int err;
2232 
2233 	/* We identify the peer by its net */
2234 	if (!info->attrs[TIPC_NLA_NET])
2235 		return -EINVAL;
2236 
2237 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2238 					  info->attrs[TIPC_NLA_NET],
2239 					  tipc_nl_net_policy, info->extack);
2240 	if (err)
2241 		return err;
2242 
2243 	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2244 	 * mutually exclusive cases
2245 	 */
2246 	if (attrs[TIPC_NLA_NET_ADDR]) {
2247 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2248 		if (!addr)
2249 			return -EINVAL;
2250 	}
2251 
2252 	if (attrs[TIPC_NLA_NET_NODEID]) {
2253 		if (!attrs[TIPC_NLA_NET_NODEID_W1])
2254 			return -EINVAL;
2255 		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2256 		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2257 		addr = hash128to32(node_id);
2258 	}
2259 
2260 	if (in_own_node(net, addr))
2261 		return -ENOTSUPP;
2262 
2263 	spin_lock_bh(&tn->node_list_lock);
2264 	peer = tipc_node_find(net, addr);
2265 	if (!peer) {
2266 		spin_unlock_bh(&tn->node_list_lock);
2267 		return -ENXIO;
2268 	}
2269 
2270 	tipc_node_write_lock(peer);
2271 	if (peer->state != SELF_DOWN_PEER_DOWN &&
2272 	    peer->state != SELF_DOWN_PEER_LEAVING) {
2273 		tipc_node_write_unlock(peer);
2274 		err = -EBUSY;
2275 		goto err_out;
2276 	}
2277 
2278 	tipc_node_clear_links(peer);
2279 	tipc_node_write_unlock(peer);
2280 	tipc_node_delete(peer);
2281 
2282 	/* Calculate cluster capabilities */
2283 	tn->capabilities = TIPC_NODE_CAPABILITIES;
2284 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2285 		tn->capabilities &= temp_node->capabilities;
2286 	}
2287 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2288 	err = 0;
2289 err_out:
2290 	tipc_node_put(peer);
2291 	spin_unlock_bh(&tn->node_list_lock);
2292 
2293 	return err;
2294 }
2295 
2296 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2297 {
2298 	int err;
2299 	struct net *net = sock_net(skb->sk);
2300 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2301 	int done = cb->args[0];
2302 	int last_addr = cb->args[1];
2303 	struct tipc_node *node;
2304 	struct tipc_nl_msg msg;
2305 
2306 	if (done)
2307 		return 0;
2308 
2309 	msg.skb = skb;
2310 	msg.portid = NETLINK_CB(cb->skb).portid;
2311 	msg.seq = cb->nlh->nlmsg_seq;
2312 
2313 	rcu_read_lock();
2314 	if (last_addr) {
2315 		node = tipc_node_find(net, last_addr);
2316 		if (!node) {
2317 			rcu_read_unlock();
2318 			/* We never set seq or call nl_dump_check_consistent()
2319 			 * this means that setting prev_seq here will cause the
2320 			 * consistence check to fail in the netlink callback
2321 			 * handler. Resulting in the NLMSG_DONE message having
2322 			 * the NLM_F_DUMP_INTR flag set if the node state
2323 			 * changed while we released the lock.
2324 			 */
2325 			cb->prev_seq = 1;
2326 			return -EPIPE;
2327 		}
2328 		tipc_node_put(node);
2329 	}
2330 
2331 	list_for_each_entry_rcu(node, &tn->node_list, list) {
2332 		if (node->preliminary)
2333 			continue;
2334 		if (last_addr) {
2335 			if (node->addr == last_addr)
2336 				last_addr = 0;
2337 			else
2338 				continue;
2339 		}
2340 
2341 		tipc_node_read_lock(node);
2342 		err = __tipc_nl_add_node(&msg, node);
2343 		if (err) {
2344 			last_addr = node->addr;
2345 			tipc_node_read_unlock(node);
2346 			goto out;
2347 		}
2348 
2349 		tipc_node_read_unlock(node);
2350 	}
2351 	done = 1;
2352 out:
2353 	cb->args[0] = done;
2354 	cb->args[1] = last_addr;
2355 	rcu_read_unlock();
2356 
2357 	return skb->len;
2358 }
2359 
2360 /* tipc_node_find_by_name - locate owner node of link by link's name
2361  * @net: the applicable net namespace
2362  * @name: pointer to link name string
2363  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2364  *
2365  * Returns pointer to node owning the link, or 0 if no matching link is found.
2366  */
2367 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2368 						const char *link_name,
2369 						unsigned int *bearer_id)
2370 {
2371 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2372 	struct tipc_link *l;
2373 	struct tipc_node *n;
2374 	struct tipc_node *found_node = NULL;
2375 	int i;
2376 
2377 	*bearer_id = 0;
2378 	rcu_read_lock();
2379 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2380 		tipc_node_read_lock(n);
2381 		for (i = 0; i < MAX_BEARERS; i++) {
2382 			l = n->links[i].link;
2383 			if (l && !strcmp(tipc_link_name(l), link_name)) {
2384 				*bearer_id = i;
2385 				found_node = n;
2386 				break;
2387 			}
2388 		}
2389 		tipc_node_read_unlock(n);
2390 		if (found_node)
2391 			break;
2392 	}
2393 	rcu_read_unlock();
2394 
2395 	return found_node;
2396 }
2397 
2398 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2399 {
2400 	int err;
2401 	int res = 0;
2402 	int bearer_id;
2403 	char *name;
2404 	struct tipc_link *link;
2405 	struct tipc_node *node;
2406 	struct sk_buff_head xmitq;
2407 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2408 	struct net *net = sock_net(skb->sk);
2409 
2410 	__skb_queue_head_init(&xmitq);
2411 
2412 	if (!info->attrs[TIPC_NLA_LINK])
2413 		return -EINVAL;
2414 
2415 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2416 					  info->attrs[TIPC_NLA_LINK],
2417 					  tipc_nl_link_policy, info->extack);
2418 	if (err)
2419 		return err;
2420 
2421 	if (!attrs[TIPC_NLA_LINK_NAME])
2422 		return -EINVAL;
2423 
2424 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2425 
2426 	if (strcmp(name, tipc_bclink_name) == 0)
2427 		return tipc_nl_bc_link_set(net, attrs);
2428 
2429 	node = tipc_node_find_by_name(net, name, &bearer_id);
2430 	if (!node)
2431 		return -EINVAL;
2432 
2433 	tipc_node_read_lock(node);
2434 
2435 	link = node->links[bearer_id].link;
2436 	if (!link) {
2437 		res = -EINVAL;
2438 		goto out;
2439 	}
2440 
2441 	if (attrs[TIPC_NLA_LINK_PROP]) {
2442 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2443 
2444 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2445 		if (err) {
2446 			res = err;
2447 			goto out;
2448 		}
2449 
2450 		if (props[TIPC_NLA_PROP_TOL]) {
2451 			u32 tol;
2452 
2453 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2454 			tipc_link_set_tolerance(link, tol, &xmitq);
2455 		}
2456 		if (props[TIPC_NLA_PROP_PRIO]) {
2457 			u32 prio;
2458 
2459 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2460 			tipc_link_set_prio(link, prio, &xmitq);
2461 		}
2462 		if (props[TIPC_NLA_PROP_WIN]) {
2463 			u32 max_win;
2464 
2465 			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2466 			tipc_link_set_queue_limits(link,
2467 						   tipc_link_min_win(link),
2468 						   max_win);
2469 		}
2470 	}
2471 
2472 out:
2473 	tipc_node_read_unlock(node);
2474 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2475 			 NULL);
2476 	return res;
2477 }
2478 
2479 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2480 {
2481 	struct net *net = genl_info_net(info);
2482 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2483 	struct tipc_nl_msg msg;
2484 	char *name;
2485 	int err;
2486 
2487 	msg.portid = info->snd_portid;
2488 	msg.seq = info->snd_seq;
2489 
2490 	if (!info->attrs[TIPC_NLA_LINK])
2491 		return -EINVAL;
2492 
2493 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2494 					  info->attrs[TIPC_NLA_LINK],
2495 					  tipc_nl_link_policy, info->extack);
2496 	if (err)
2497 		return err;
2498 
2499 	if (!attrs[TIPC_NLA_LINK_NAME])
2500 		return -EINVAL;
2501 
2502 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2503 
2504 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2505 	if (!msg.skb)
2506 		return -ENOMEM;
2507 
2508 	if (strcmp(name, tipc_bclink_name) == 0) {
2509 		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2510 		if (err)
2511 			goto err_free;
2512 	} else {
2513 		int bearer_id;
2514 		struct tipc_node *node;
2515 		struct tipc_link *link;
2516 
2517 		node = tipc_node_find_by_name(net, name, &bearer_id);
2518 		if (!node) {
2519 			err = -EINVAL;
2520 			goto err_free;
2521 		}
2522 
2523 		tipc_node_read_lock(node);
2524 		link = node->links[bearer_id].link;
2525 		if (!link) {
2526 			tipc_node_read_unlock(node);
2527 			err = -EINVAL;
2528 			goto err_free;
2529 		}
2530 
2531 		err = __tipc_nl_add_link(net, &msg, link, 0);
2532 		tipc_node_read_unlock(node);
2533 		if (err)
2534 			goto err_free;
2535 	}
2536 
2537 	return genlmsg_reply(msg.skb, info);
2538 
2539 err_free:
2540 	nlmsg_free(msg.skb);
2541 	return err;
2542 }
2543 
2544 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2545 {
2546 	int err;
2547 	char *link_name;
2548 	unsigned int bearer_id;
2549 	struct tipc_link *link;
2550 	struct tipc_node *node;
2551 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2552 	struct net *net = sock_net(skb->sk);
2553 	struct tipc_net *tn = tipc_net(net);
2554 	struct tipc_link_entry *le;
2555 
2556 	if (!info->attrs[TIPC_NLA_LINK])
2557 		return -EINVAL;
2558 
2559 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2560 					  info->attrs[TIPC_NLA_LINK],
2561 					  tipc_nl_link_policy, info->extack);
2562 	if (err)
2563 		return err;
2564 
2565 	if (!attrs[TIPC_NLA_LINK_NAME])
2566 		return -EINVAL;
2567 
2568 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2569 
2570 	err = -EINVAL;
2571 	if (!strcmp(link_name, tipc_bclink_name)) {
2572 		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2573 		if (err)
2574 			return err;
2575 		return 0;
2576 	} else if (strstr(link_name, tipc_bclink_name)) {
2577 		rcu_read_lock();
2578 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2579 			tipc_node_read_lock(node);
2580 			link = node->bc_entry.link;
2581 			if (link && !strcmp(link_name, tipc_link_name(link))) {
2582 				err = tipc_bclink_reset_stats(net, link);
2583 				tipc_node_read_unlock(node);
2584 				break;
2585 			}
2586 			tipc_node_read_unlock(node);
2587 		}
2588 		rcu_read_unlock();
2589 		return err;
2590 	}
2591 
2592 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2593 	if (!node)
2594 		return -EINVAL;
2595 
2596 	le = &node->links[bearer_id];
2597 	tipc_node_read_lock(node);
2598 	spin_lock_bh(&le->lock);
2599 	link = node->links[bearer_id].link;
2600 	if (!link) {
2601 		spin_unlock_bh(&le->lock);
2602 		tipc_node_read_unlock(node);
2603 		return -EINVAL;
2604 	}
2605 	tipc_link_reset_stats(link);
2606 	spin_unlock_bh(&le->lock);
2607 	tipc_node_read_unlock(node);
2608 	return 0;
2609 }
2610 
2611 /* Caller should hold node lock  */
2612 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2613 				    struct tipc_node *node, u32 *prev_link,
2614 				    bool bc_link)
2615 {
2616 	u32 i;
2617 	int err;
2618 
2619 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2620 		*prev_link = i;
2621 
2622 		if (!node->links[i].link)
2623 			continue;
2624 
2625 		err = __tipc_nl_add_link(net, msg,
2626 					 node->links[i].link, NLM_F_MULTI);
2627 		if (err)
2628 			return err;
2629 	}
2630 
2631 	if (bc_link) {
2632 		*prev_link = i;
2633 		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2634 		if (err)
2635 			return err;
2636 	}
2637 
2638 	*prev_link = 0;
2639 
2640 	return 0;
2641 }
2642 
2643 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2644 {
2645 	struct net *net = sock_net(skb->sk);
2646 	struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2647 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2648 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2649 	struct tipc_node *node;
2650 	struct tipc_nl_msg msg;
2651 	u32 prev_node = cb->args[0];
2652 	u32 prev_link = cb->args[1];
2653 	int done = cb->args[2];
2654 	bool bc_link = cb->args[3];
2655 	int err;
2656 
2657 	if (done)
2658 		return 0;
2659 
2660 	if (!prev_node) {
2661 		/* Check if broadcast-receiver links dumping is needed */
2662 		if (attrs && attrs[TIPC_NLA_LINK]) {
2663 			err = nla_parse_nested_deprecated(link,
2664 							  TIPC_NLA_LINK_MAX,
2665 							  attrs[TIPC_NLA_LINK],
2666 							  tipc_nl_link_policy,
2667 							  NULL);
2668 			if (unlikely(err))
2669 				return err;
2670 			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2671 				return -EINVAL;
2672 			bc_link = true;
2673 		}
2674 	}
2675 
2676 	msg.skb = skb;
2677 	msg.portid = NETLINK_CB(cb->skb).portid;
2678 	msg.seq = cb->nlh->nlmsg_seq;
2679 
2680 	rcu_read_lock();
2681 	if (prev_node) {
2682 		node = tipc_node_find(net, prev_node);
2683 		if (!node) {
2684 			/* We never set seq or call nl_dump_check_consistent()
2685 			 * this means that setting prev_seq here will cause the
2686 			 * consistence check to fail in the netlink callback
2687 			 * handler. Resulting in the last NLMSG_DONE message
2688 			 * having the NLM_F_DUMP_INTR flag set.
2689 			 */
2690 			cb->prev_seq = 1;
2691 			goto out;
2692 		}
2693 		tipc_node_put(node);
2694 
2695 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2696 						 list) {
2697 			tipc_node_read_lock(node);
2698 			err = __tipc_nl_add_node_links(net, &msg, node,
2699 						       &prev_link, bc_link);
2700 			tipc_node_read_unlock(node);
2701 			if (err)
2702 				goto out;
2703 
2704 			prev_node = node->addr;
2705 		}
2706 	} else {
2707 		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2708 		if (err)
2709 			goto out;
2710 
2711 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2712 			tipc_node_read_lock(node);
2713 			err = __tipc_nl_add_node_links(net, &msg, node,
2714 						       &prev_link, bc_link);
2715 			tipc_node_read_unlock(node);
2716 			if (err)
2717 				goto out;
2718 
2719 			prev_node = node->addr;
2720 		}
2721 	}
2722 	done = 1;
2723 out:
2724 	rcu_read_unlock();
2725 
2726 	cb->args[0] = prev_node;
2727 	cb->args[1] = prev_link;
2728 	cb->args[2] = done;
2729 	cb->args[3] = bc_link;
2730 
2731 	return skb->len;
2732 }
2733 
2734 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2735 {
2736 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2737 	struct net *net = sock_net(skb->sk);
2738 	int err;
2739 
2740 	if (!info->attrs[TIPC_NLA_MON])
2741 		return -EINVAL;
2742 
2743 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2744 					  info->attrs[TIPC_NLA_MON],
2745 					  tipc_nl_monitor_policy,
2746 					  info->extack);
2747 	if (err)
2748 		return err;
2749 
2750 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2751 		u32 val;
2752 
2753 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2754 		err = tipc_nl_monitor_set_threshold(net, val);
2755 		if (err)
2756 			return err;
2757 	}
2758 
2759 	return 0;
2760 }
2761 
2762 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2763 {
2764 	struct nlattr *attrs;
2765 	void *hdr;
2766 	u32 val;
2767 
2768 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2769 			  0, TIPC_NL_MON_GET);
2770 	if (!hdr)
2771 		return -EMSGSIZE;
2772 
2773 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2774 	if (!attrs)
2775 		goto msg_full;
2776 
2777 	val = tipc_nl_monitor_get_threshold(net);
2778 
2779 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2780 		goto attr_msg_full;
2781 
2782 	nla_nest_end(msg->skb, attrs);
2783 	genlmsg_end(msg->skb, hdr);
2784 
2785 	return 0;
2786 
2787 attr_msg_full:
2788 	nla_nest_cancel(msg->skb, attrs);
2789 msg_full:
2790 	genlmsg_cancel(msg->skb, hdr);
2791 
2792 	return -EMSGSIZE;
2793 }
2794 
2795 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2796 {
2797 	struct net *net = sock_net(skb->sk);
2798 	struct tipc_nl_msg msg;
2799 	int err;
2800 
2801 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2802 	if (!msg.skb)
2803 		return -ENOMEM;
2804 	msg.portid = info->snd_portid;
2805 	msg.seq = info->snd_seq;
2806 
2807 	err = __tipc_nl_add_monitor_prop(net, &msg);
2808 	if (err) {
2809 		nlmsg_free(msg.skb);
2810 		return err;
2811 	}
2812 
2813 	return genlmsg_reply(msg.skb, info);
2814 }
2815 
2816 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2817 {
2818 	struct net *net = sock_net(skb->sk);
2819 	u32 prev_bearer = cb->args[0];
2820 	struct tipc_nl_msg msg;
2821 	int bearer_id;
2822 	int err;
2823 
2824 	if (prev_bearer == MAX_BEARERS)
2825 		return 0;
2826 
2827 	msg.skb = skb;
2828 	msg.portid = NETLINK_CB(cb->skb).portid;
2829 	msg.seq = cb->nlh->nlmsg_seq;
2830 
2831 	rtnl_lock();
2832 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2833 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2834 		if (err)
2835 			break;
2836 	}
2837 	rtnl_unlock();
2838 	cb->args[0] = bearer_id;
2839 
2840 	return skb->len;
2841 }
2842 
2843 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2844 				   struct netlink_callback *cb)
2845 {
2846 	struct net *net = sock_net(skb->sk);
2847 	u32 prev_node = cb->args[1];
2848 	u32 bearer_id = cb->args[2];
2849 	int done = cb->args[0];
2850 	struct tipc_nl_msg msg;
2851 	int err;
2852 
2853 	if (!prev_node) {
2854 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2855 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2856 
2857 		if (!attrs[TIPC_NLA_MON])
2858 			return -EINVAL;
2859 
2860 		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2861 						  attrs[TIPC_NLA_MON],
2862 						  tipc_nl_monitor_policy,
2863 						  NULL);
2864 		if (err)
2865 			return err;
2866 
2867 		if (!mon[TIPC_NLA_MON_REF])
2868 			return -EINVAL;
2869 
2870 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2871 
2872 		if (bearer_id >= MAX_BEARERS)
2873 			return -EINVAL;
2874 	}
2875 
2876 	if (done)
2877 		return 0;
2878 
2879 	msg.skb = skb;
2880 	msg.portid = NETLINK_CB(cb->skb).portid;
2881 	msg.seq = cb->nlh->nlmsg_seq;
2882 
2883 	rtnl_lock();
2884 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2885 	if (!err)
2886 		done = 1;
2887 
2888 	rtnl_unlock();
2889 	cb->args[0] = done;
2890 	cb->args[1] = prev_node;
2891 	cb->args[2] = bearer_id;
2892 
2893 	return skb->len;
2894 }
2895 
2896 #ifdef CONFIG_TIPC_CRYPTO
2897 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2898 				struct tipc_aead_key **key)
2899 {
2900 	struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2901 
2902 	if (!attr)
2903 		return -ENODATA;
2904 
2905 	*key = (struct tipc_aead_key *)nla_data(attr);
2906 	if (nla_len(attr) < tipc_aead_key_size(*key))
2907 		return -EINVAL;
2908 
2909 	return 0;
2910 }
2911 
2912 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2913 {
2914 	struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2915 
2916 	if (!attr)
2917 		return -ENODATA;
2918 
2919 	if (nla_len(attr) < TIPC_NODEID_LEN)
2920 		return -EINVAL;
2921 
2922 	*node_id = (u8 *)nla_data(attr);
2923 	return 0;
2924 }
2925 
2926 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2927 {
2928 	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2929 
2930 	if (!attr)
2931 		return -ENODATA;
2932 
2933 	*intv = nla_get_u32(attr);
2934 	return 0;
2935 }
2936 
2937 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2938 {
2939 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2940 	struct net *net = sock_net(skb->sk);
2941 	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2942 	struct tipc_node *n = NULL;
2943 	struct tipc_aead_key *ukey;
2944 	bool rekeying = true, master_key = false;
2945 	u8 *id, *own_id, mode;
2946 	u32 intv = 0;
2947 	int rc = 0;
2948 
2949 	if (!info->attrs[TIPC_NLA_NODE])
2950 		return -EINVAL;
2951 
2952 	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2953 			      info->attrs[TIPC_NLA_NODE],
2954 			      tipc_nl_node_policy, info->extack);
2955 	if (rc)
2956 		return rc;
2957 
2958 	own_id = tipc_own_id(net);
2959 	if (!own_id) {
2960 		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
2961 		return -EPERM;
2962 	}
2963 
2964 	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
2965 	if (rc == -ENODATA)
2966 		rekeying = false;
2967 
2968 	rc = tipc_nl_retrieve_key(attrs, &ukey);
2969 	if (rc == -ENODATA && rekeying)
2970 		goto rekeying;
2971 	else if (rc)
2972 		return rc;
2973 
2974 	rc = tipc_aead_key_validate(ukey, info);
2975 	if (rc)
2976 		return rc;
2977 
2978 	rc = tipc_nl_retrieve_nodeid(attrs, &id);
2979 	switch (rc) {
2980 	case -ENODATA:
2981 		mode = CLUSTER_KEY;
2982 		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
2983 		break;
2984 	case 0:
2985 		mode = PER_NODE_KEY;
2986 		if (memcmp(id, own_id, NODE_ID_LEN)) {
2987 			n = tipc_node_find_by_id(net, id) ?:
2988 				tipc_node_create(net, 0, id, 0xffffu, 0, true);
2989 			if (unlikely(!n))
2990 				return -ENOMEM;
2991 			c = n->crypto_rx;
2992 		}
2993 		break;
2994 	default:
2995 		return rc;
2996 	}
2997 
2998 	/* Initiate the TX/RX key */
2999 	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3000 	if (n)
3001 		tipc_node_put(n);
3002 
3003 	if (unlikely(rc < 0)) {
3004 		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3005 		return rc;
3006 	} else if (c == tx) {
3007 		/* Distribute TX key but not master one */
3008 		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3009 			GENL_SET_ERR_MSG(info, "failed to replicate new key");
3010 rekeying:
3011 		/* Schedule TX rekeying if needed */
3012 		tipc_crypto_rekeying_sched(tx, rekeying, intv);
3013 	}
3014 
3015 	return 0;
3016 }
3017 
3018 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3019 {
3020 	int err;
3021 
3022 	rtnl_lock();
3023 	err = __tipc_nl_node_set_key(skb, info);
3024 	rtnl_unlock();
3025 
3026 	return err;
3027 }
3028 
3029 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3030 				    struct genl_info *info)
3031 {
3032 	struct net *net = sock_net(skb->sk);
3033 	struct tipc_net *tn = tipc_net(net);
3034 	struct tipc_node *n;
3035 
3036 	tipc_crypto_key_flush(tn->crypto_tx);
3037 	rcu_read_lock();
3038 	list_for_each_entry_rcu(n, &tn->node_list, list)
3039 		tipc_crypto_key_flush(n->crypto_rx);
3040 	rcu_read_unlock();
3041 
3042 	return 0;
3043 }
3044 
3045 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3046 {
3047 	int err;
3048 
3049 	rtnl_lock();
3050 	err = __tipc_nl_node_flush_key(skb, info);
3051 	rtnl_unlock();
3052 
3053 	return err;
3054 }
3055 #endif
3056 
3057 /**
3058  * tipc_node_dump - dump TIPC node data
3059  * @n: tipc node to be dumped
3060  * @more: dump more?
3061  *        - false: dump only tipc node data
3062  *        - true: dump node link data as well
3063  * @buf: returned buffer of dump data in format
3064  */
3065 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3066 {
3067 	int i = 0;
3068 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3069 
3070 	if (!n) {
3071 		i += scnprintf(buf, sz, "node data: (null)\n");
3072 		return i;
3073 	}
3074 
3075 	i += scnprintf(buf, sz, "node data: %x", n->addr);
3076 	i += scnprintf(buf + i, sz - i, " %x", n->state);
3077 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3078 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3079 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3080 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3081 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3082 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3083 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3084 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3085 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3086 
3087 	if (!more)
3088 		return i;
3089 
3090 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3091 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3092 	i += scnprintf(buf + i, sz - i, " media: ");
3093 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3094 	i += scnprintf(buf + i, sz - i, "\n");
3095 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3096 	i += scnprintf(buf + i, sz - i, " inputq: ");
3097 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3098 
3099 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3100 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3101 	i += scnprintf(buf + i, sz - i, " media: ");
3102 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3103 	i += scnprintf(buf + i, sz - i, "\n");
3104 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3105 	i += scnprintf(buf + i, sz - i, " inputq: ");
3106 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3107 
3108 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
3109 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3110 
3111 	return i;
3112 }
3113 
3114 void tipc_node_pre_cleanup_net(struct net *exit_net)
3115 {
3116 	struct tipc_node *n;
3117 	struct tipc_net *tn;
3118 	struct net *tmp;
3119 
3120 	rcu_read_lock();
3121 	for_each_net_rcu(tmp) {
3122 		if (tmp == exit_net)
3123 			continue;
3124 		tn = tipc_net(tmp);
3125 		if (!tn)
3126 			continue;
3127 		spin_lock_bh(&tn->node_list_lock);
3128 		list_for_each_entry_rcu(n, &tn->node_list, list) {
3129 			if (!n->peer_net)
3130 				continue;
3131 			if (n->peer_net != exit_net)
3132 				continue;
3133 			tipc_node_write_lock(n);
3134 			n->peer_net = NULL;
3135 			n->peer_hash_mix = 0;
3136 			tipc_node_write_unlock_fast(n);
3137 			break;
3138 		}
3139 		spin_unlock_bh(&tn->node_list_lock);
3140 	}
3141 	rcu_read_unlock();
3142 }
3143